Componentes não-integrantes da carcaça de bovinos de três grupos genéticos terminados em confinamento ou pastejo rotacionado com suplementação.

Foram avaliados os componentes não-integrantes da carcaça de bovinos castrados (novilhos) Brahman, Brangus e Hereford terminados em confinamento ou pastejo com suplementação (capim-mombaça). Os animais foram abatidos com espessura de gordura subcutânea superior a 4mm. A dieta do confinamento foi formulada com 60% de volumoso e 40% de concentrado, com 13% PB e 62% NDT. O capim mombaça apresentou 7% de PB e 56%NDT e o suplemento apresentou 24% PB e 76% NDT. O delineamento experimental foi inteiramente casualizado, com arranjo fatorial 3x2 (três grupos genéticos e dois sistemas de terminação) e as médias foram comparadas pelo teste de Tukey ajustado. Foram observadas diferenças significativas para o peso de abate (PA) e peso do corpo vazio (PCV) favorável aos animais mantidos em pastejo com suplementação (444,03 vs 416,50kg para PA e 409,68 vs 375,24kg para PCV), entretanto não houve diferença significativa entre os sistemas de terminação para o rendimento de corpo vazio (RCV). O menor percentual de órgãos vitais foi apresentado pela raça Brahman independente do sistema de terminação utilizado (2,19%). A mesma tendência foi observada para o trato digestivo com um percentual de participação de 3,77% PCV do Brahman vs 4,87% e 4,48% PCV do Hereford e Brangus, respectivamente. Os novilhos Brahman apresentaram menores pesos de coração, pulmão e baço que os Hereford e Brangus. Os animais terminados em pastejo apresentaram maiores pesos de abomaso, pulmão e rins que os terminados em confinamento, 0,47 vs 0,35% PCV; 0,77 vs 0,71% PCV e 0,77 vs 0,71% PCV, respectivamente

Oncogenic c-Myc induces replication stress by increasing cohesins chromatin occupancy in a CTCF-dependent manner.

Oncogene-induced replication stress is a crucial driver of genomic instability and one of the key events contributing to the onset and evolution of cancer. Despite its critical role in cancer, the mechanisms that generate oncogene-induced replication stress remain not fully understood. Here, we report that an oncogenic c-Myc-dependent increase in cohesins on DNA contributes to the induction of replication stress. Accumulation of cohesins on chromatin is not sufficient to cause replication stress, but also requires cohesins to accumulate at specific sites in a CTCF-dependent manner. We propose that the increased accumulation of cohesins at CTCF site interferes with the progression of replication forks, contributing to oncogene-induced replication stress. This is different from, and independent of, previously suggested mechanisms of oncogene-induced replication stress. This, together with the reported protective role of cohesins in preventing replication stress-induced DNA damage, supports a double-edge involvement of cohesins in causing and tolerating oncogene-induced replication stress

Physiological and thermographic response to heat stress in zebu cattle

AbstractThe objective of this study was to evaluate the heat tolerance of five zebu breeds using physical, physiological and hematological traits as well as thermographic responses. Forty cows of the Gir, Girolando, Nelore, Sindhi and Indubrasil breeds (eight cows each), approximately three years of age, were evaluated. Body weight, withers and hump heights as well as thoracic circumference were recorded. The density and length of the hair was obtained by collecting one square centimeter in the rump region and skin color using the CIELAB system. Rectal temperature, heart and respiratory rates were evaluated during the morning at 4:30h, and in the afternoon, at 14:30h, with six repetitions. Blood samples were collected for hematological evaluation. The surface temperature was obtained using an infrared camera FLIR® T400. Two images were taken from each animal, one laterally of the whole body and the other of the head region. Air temperature, wind speed, relative humidity were obtained from a mobile weather station. The statistics analysis included an analyzes of variance, principal factors, as well as cluster, discriminant and canonical analyzes, logistic regression and calculation of odds ratio. There were significant differences in the rectal temperature, heart and respiratory rates between breeds. Gir and Indubrasil breeds had the highest rectal temperatures. Breed was significant for surface temperatures and showed that physical and physiological factors affected breeds in different ways. Eye and brain surface temperatures were the most affected by environmental parameters. Also, environmental parameters affected packed cell volume and red cell number. Odds ratio test showed that the Gir breed was three times more likely to have higher rectal temperature compared with Sindhi as confirmed by the logistic regression. When the black globe temperature approached 35°C, the probability of the Gir animals having rectal temperatures above normal was approximately 70%. Gir was the breed least adapted to climate conditions of the experiment while the Sindhi and Girolando breeds showed the best physiological response to thermal stress

Nutritional and quality changes in piglet concentrate affected by the mix.

Abstract: The aim of this study was to evaluate the reasons of quality deviation of a concentrate from a predefined standard. Five treatments were established: T1 - Control, standard concentrate formulation (SCF); T2 - PXMore5, SCF with more 5% vitamin-mineral premix (VMP); T3 - PXLess5, SCF with less 5% VMP. All three treatments used a 400kg batches in an INTECNIAL mixer; T4 - FeedMixer, SCF using a 4,000kg batch in an IMOTO mixer; T5 - PremixMixer, SCF using a 1,200kg batch in an MUYANG mixer. For each treatment, bags of 20 kg were stored in three storage places for four months. Water activity of concentrate was affected by temperature and air relative humidity in different storage places. Regarding the kind of mixer, the greatest variation in concentration of crude protein, mineral residue, copper, zinc, and selenium was observed in the PremixMixer. Adjustments are imperative in the handling and use procedures of this kind of mixer to meet the quality requirements required in the concentrate production. Analyzing the effect of the mineral-vitamin premix level, no difference could be defined with the evaluated parameters. Resumo: O objetivo deste estudo foi avaliar as razões do desvio de qualidade de um concentrado de um padrão predefinido. Foram estabelecidos cinco tratamentos: T1 - controle, concentrado com formulação padrão (CFP); T2 - PXMais5, CFP com 5% a mais de vitaminas e minerais da pré-mistura (PVM); T3 - PXMenos5, CFP com 5% a menos de PVM. Todos esses três tratamentos utilizaram lotes de 400kg em um misturador INTECNIAL; T4 - FeedMixer, CFP usando um lote de 4.000kg em um misturador IMOTO; T5 - PremixMixer, CFP usando um lote de 1.200kg em um misturador MUYANG. Para cada tratamento, sacos de 20kg foram armazenados em três ambientes distintos por quatro meses. A atividade de água do concentrado foi afetada pela temperatura e umidade relativa do ar em diferentes locais de armazenamento. Em relação ao tipo de misturador, a maior variação na concentração de proteína bruta, resíduo mineral, cobre, zinco e selênio foi devido ao PremixMixer. Ajustes são imperativos nos procedimentos de manuseio e uso desse tipo de misturador para atender aos requisitos de qualidade exigidos na produção de concentrado. Ao se analisar o efeito do nível da pré-mistura de vitaminas e minerais, nenhuma diferença pôde ser definida com os parâmetros avaliados

Nutritional and quality changes in piglet concentrate affected by formulation and storage.

Abstract: The aim of this study was to evaluate the variations in the stability and nutrient concentration in concentrates for piglet feeding. Five treatments were established: T1 - Control, standard concentrate formulation (SCF); T2 - PXMore5, SCF with more 5% vitamin-mineral premix (VMP); T3 - PXLess5, SCF with less 5% VMP. All these three treatments used 400kg batches in an INTECNIAL mixer; T4 - FeedMixer, SCF using a 4,000kg batch in an IMOTO mixer; T5 - PremixMixer, SCF using a 1,200kg batch in an MUYANG mixer. For each treatment, bags of 20kg were stored in three storage places for four months where room temperature and relative humidity was recorded daily. The concentration of nutrients was evaluated through centesimal and mineral analysis. The water activity of concentrate was affected by temperature and relative air humidity in different storage places. The greatest variation in concentration of crude protein, mineral residue, copper, zinc, and selenium was due to the PremixMixer treatment. Regarding the guaranteed levels, the critical value was verified only for the chrome concentration. Resumo: O objetivo deste estudo foi avaliar as variações na estabilidade e na concentração de nutrientes em concentrados para alimentação de leitões. Foram estabelecidos cinco tratamentos: T1 - controle, concentrado com formulação padrão (CFP); T2 - PXMais5, CFP com 5% a mais de vitaminas e minerais da pré-mistura (PVM); T3 - PXMenos5, CFP com 5% a menos de PVM (todos os três tratamentos utilizaram lotes de 400kg em um misturador INTECNIAL); T4 - FeedMixer, CFP usando um lote de 4.000kg em um misturador IMOTO; T5 - PremixMixer, CFP usando um lote de 1.200kg em um misturador MUYANG. Para cada tratamento, sacos de 20kg foram armazenados em três ambientes distintos por quatro meses, onde a temperatura ambiente e a umidade relativa do ar foram registradas diariamente. A concentração de nutrientes foi avaliada por meio de análises centesimal e mineral. A atividade de água do concentrado foi afetada pela temperatura e a umidade relativa do ar nos diferentes locais de armazenamento. A maior variação na concentração de proteína bruta, resíduo mineral, cobre, zinco e selênio foi devido ao tratamento ?MistPremix?. Em relação aos níveis de garantia, foi verificado valor crítico apenas para a concentração de cromo

Elevated temperature-humidity index induces physiological, blood and milk alterations in Holstein cows in a more pronounced manner than in ½ and ¾ Holstein × Gir.

Bos taurus taurus and Bos taurus indicus cattle subspecies present different capabilities in coping with situations of elevated temperatures, the latter being more tolerant to heat stress. Thus, some breeding programs crossed these subspecies to produce a high producing yet heat-tolerant breed (Girolando). Nineteen Holstein (H100) and 19 Girolando cows [(½ Holstein × Gir (H50) and ¾ Holstein × Gir (H75)] with similar milk production were used in a six-day experiment to evaluate the consequences of heat stress due to shade deprivation on their physiological, blood and milk traits. Cows were exposed to a non-shaded environment between morning (06:00h; GMT -3:00) and evening milking (14:30h; GMT -3:00) with access to water ad libitum. Procedures were conducted before morning and evening milkings. Physiological parameters related to mechanisms of heat dissipation were measured, as well as the milk composition. Blood traits were evaluated. The temperature-humidity index (THI) was calculated. Statistical procedures included analysis of variance, correlation, and principal factors. THI was elevated during the trial and negatively impacted physiological, milk, and blood parameters in H100, H75, and H50. Alterations in physiology, milk stability, milk composition, and blood traits were more pronounced in H100. Holstein cows presented changes in physiological parameters in a more pronounced manner and in some milk and blood traits related to the reduced capability of this breed in dealing with elevated THI. The similarity in milk production levels excludes this parameter as a justification for differences in heat tolerance, with genetic composition being the main reason for these results

Assessment of copy number variants in three Brazilian locally adapted cattle breeds using whole-genome re-sequencing data.

Further characterization of genetic structural variations should strongly focus on small and endangered local breeds given their role in unraveling genes and structural variants underlying selective pressures and phenotype variation. A comprehensive genome-wide assessment of copy number variations (CNVs) based on whole-genome re-sequencing data was performed on three Brazilian locally adapted cattle breeds (Caracu Caldeano, Crioulo Lageano, and Pantaneiro) using the ARS-UCD1.2 genome assembly. Data from 36 individuals with an average coverage depth of 14.07× per individual was used. A total of 24?945 CNVs were identified distributed among the breeds (Caracu Caldeano = 7285, Crioulo Lageano = 7297, and Pantaneiro = 10 363). Deletion events were 1.75?2.07-fold higher than duplications, and the total length of CNVs is composed mostly of a high number of segments between 10 and 30?kb. CNV regions (CNVRs) are not uniformly scattered throughout the genomes (n = 463), and 105 CNVRs were found overlapping among the studied breeds. Functional annotation of the CNVRs revealed variants with high consequence on protein sequence harboring relevant genes, in which we highlighted the BOLA-DQB, BOLA-DQA5, CD1A, ?-defensins, PRG3, and ULBP21 genes. Enrichment analysis based on the gene list retrieved from the CNVRs disclosed over-represented terms (p?<?0.01) strongly associated with immunity and cattle resilience to harsh environments. Additionally, QTL associated with body conformation and dairy-related traits were also unveiled within the CNVRs. These results provide better understanding of the selective forces shaping the genome of such cattle breeds and identify traces of natural selection pressures by which these populations have been exposed to challenging environmental conditions.First online